Improvement in steam-generators



`N.'P. BRIGHTMAN.

I Steam-Generators. N0. 138,607. Patented May 6.1873.

@finesses Q @w W UNITED STATES `PATENT QFFICE.

NATHAN P. BRIGHTMAN, OF NEW BEDFORD, MASSACHUSETTS.

IMPROVEMENT IN STEAM-GENERATORS.

Y Specification forming part of Letters Patent No. 138,607, dated May 6, 1873; application filed February 21, 1873.

To all whom it may concern:

Be it known that I, NATHAN 1?. BRIGHTMAN,

`of New Bedford, in the county of Bristol and t vide a simple, cheap, and effective means for utilizing a greater amount of the heat generated in the furnace or combustion-chamber of a steam-boiler than has heretofore been done, by applying the heat to the apparatus in such manner that small portions only of the water in the generator is subjected to the action of the greatest amount of heat, and the water immediately converted into steam, thereby generatin g steam iu less time and with greater econom y; and, furthermore, by arranging the heating-surfaces in such manner that they will defleet the heat from one to the other, and thus keep up an active circulation of theheat to fully utilize and transmit it to the water of the boiler; and to these ends my improvement consists, rst, in arranging a spiral conical coil of pipe within the furnace of a boiler, and connecting its lower end to the lower portion or waterleg of the boiler, and carrying its other extremity through the crown-sheet to a point above the water-line, or to the steam-dome ofthe boiler, in the manner and for the purpose hereinafter more fully set forth; second, -in forming the walls ofnthe lire-ch amber that surrounds the conical coil into a frustum of a cone, the angle of its sides being more acute than the angle of the sides of the coil, so that the space between them will be enlarged proportionately to accommodate the increasing volume of the products of combustion that pass between the coils as they ascend, as hereinafter described; third, in combining the conical coil, arranged and applied to a boiler substantially as described, with a hood secured at or near its apex, that serves to deiect the heated current of gases, and thus prevent their direct exit through the smoke-stack, as hereinafter more relate particularly to vertical cylindrical boilers, the outer shell A of which is formed in the usual way. The lower portion B of the inner shell, from a point just above the furnace-door to the base or bed-plate--not shown inthe drawingis also cylindrical, and placed concentrically to the outer shell, and leaving an annular space of suitable width between them, which forms the water-leg of the boiler. The upper portion B,of the inner shell is formed of another plate of boiler-iron riveted to the lower plate, and made conical orlike a frustum of a cone, the crown-plate C being riveted to its upper edge in a simple and effectual manner. The smokestack D is secured to the crown-plate at its cen ter by an angle-iron ring, and passes through the center ofthe cap of the outer casing, thus forming a water-and-steam space, E, between the outer and inner casing, and a fire-chamber, F, communicatin g with the chimney within the inner casing in a well-known manner. A conical spiral coil of pipe, Gr, of suitable size and material, is connected at its lower end, by a screw-coupling, to the lower part or water-leg of the boiler 5 andis connected, in asimilar manner, to a vertical tube that passes through the crown-plate and terminates in the upper part or steam-dome of the boiler. By this means the coil can be readily secured to or detached from the boiler when` desired.

It will be seen, by reference to the drawing, that the taper of the coil is more or less acute than that ofthe conical part B of the inner casing that surrounds it. The object of this t mode of construction is to form a gradually-increasing space between the outer part of the coil and the surrounding case, in order that the heated currents, in passing through the interstices of each layer or coil of pipe, will not be obstructed or choked in their movements.

A hood, H, of peculiar form, is secured to the top of the coil in such manner as to obstruct the heated currents of the fire-chamber, and prevent their direct exit through the smoke-stack.

The deflector may be secured to the crownplate by a bolt 5 but I prefer to make it in the peculiar shape shown in the detached gure of the drawing, and which permits it to be screwed in between the coils of the pipe, and readily attached or detached'when desired.

The movements ofthe heated currents of the 2 resaca? products of combustion form an im portant function in the generation of steam with the abovedescribed apparatus, and will require a short description: The coils of pipe being arranged, one above the other, in such manner that the outer surface of the pipe will slightly overlap the inner surface of the coil beneath it, so that the heated currents, which move in a vertical or nearly vertical direction, will not pass directly between the coils and against the inner casing of the boiler,but will first strike the b ottom of the pipe, and be deflected to each side, a portion against the inner casing of the boiler, and another portion toward the center and apex of the coil, as each space between the layers of pipe conducts a certain quantity of gases to the annular space between thepipe and casin g and it will be readily seen that the gases will accumulate as each layer is added, and will require agradual enlargement of said space to prevent the currents from bein g choked or retarded in their movements.

By this means the same heated currents are appliedand deflected from surface to surface, and most eli'ectually utilized. The currents deiiected toward the center of the coil are concentrated at the apex ofthe same and, by theirincreased volume and intensity, serve to heat the upper layers ofthe coil of pipes to a much greater degree than the lower layer, thus subjecting small quantities of water to the most intense heat, and converted almost instantly into steam 5 whichis conveyed directly to the steamdome or upper portion ofthe boiler instead of passing through the water of the boiler, and serving merely to impart to it latent heat, Which would require the whole body of water to be heated to the boiling-point, or 2120, before steam is generated.

Tater-gages, safety-valves, and other well-- known appliances are attached to form the complete boiler, and need no description here, as they form no part of the subject-matter herein claimed.

I do not claim, broadly, the arrangement of a coil of pipe within a boiler-furnace, connected at one end to the water-leg, and at the other end to the steam-dome of the boiler, as this is Well known.

I claim as my invention and desire to secure by Letters Patent- 1. The combination and arrangement of a conical spiral coil of pipe Within the furnace of a steam-boiler, the/lower end of the coil being connected to the lower part of boiler, and the upper end passing through the crown-sheet,and terminating in the steam-space of the boiler, substantially as and for purpose set forth.

2. The combination of said conical coil ot' pipe, in the manner described, with the furnace of a steam-boiler, the walls of which are coned with less taper than that ot' the coil of pipes, so that an annular expanding space is left between them, substantially as described, for the. purpose specified.

3. The combination of the coil, arranged within the furnace ot' a steam-boiler, with the hood or deilector placed near the apex of the conical coil to deflect the heat and names, and prevent their direct exit through the smokestack, substantially as described.

NATHAN P.V BRIGHTMAN.

Vitnesses:

G. C. POOLE, B. H. lVloRsE. 

